Prosthetic foot for injured or short legs



7 y 27, 4 M. CAPELLA VALENTl 2,446,042

' Filed Jan; 17. 1946 PROS'I'HETIC FOOT FOR INJURED 0R SHORT LEGS 2 Sheets-Sheet l July 27, 19 8- M. COIAPELL'A- VVALENTI v PROS'IHETIC FOOT FOR INJURED OR SHORT LEGS Filed Jan. 1'7, 1946 2 Sheets-Sheet 2 other convenient material and Patented July 27, 1948 PROSTHETIC FOOT FOR INJURED OR SHORT LEGS Mario Capella V'alenti, Barcelona, Spain Application January 17, 1946, Serial No. 641,729

In Spain February '7, 1945 7 Claims.

My invention consists a prosthetic or arti- 1 ficial foot which may be applied to injured or short legs. It may be also applied to patients who have a marked shortness of a leg with a more or less important deformity in their foot. By my apparatus they are able in both cases to walk normally. 7

One of the objects of my invention is to obtain a prosthetic foot than can easily be applied to the injured who have lost one or both feet. This prosthetic foot, once applied, would allow them to make the movements that are made in normal walking, so permitting them to walk nearly as well as before the injury.

.Another object of my invention isthe possibility of applying this prosthetic foot'to patients who have a marked shortness of one leg, so that these patients may also walk without suffering from the difference in the length of their legs.

'With these objects in view, my invention consists of a prosthetic or artificial foot formed of difierent parts which are conveniently articu- I lated and combined by a special mechanism, so that, when walking, the movements made are those made by a normal foot. If the prosthetic foot is applied to an injured person it is set, by an articulation, on a framing or rigid part, constituting an artificial shin portion which is fastened in a convenient way to the portion of the leg that has been left to the injured person. This framing has to be made specially in every case in order to get theform and size required to be applied to this part of the leg. If the prosthetic foot is intended for a person who has one of his legs much shorter than the other, or whose foot or leg is deformed, then, the prosthetic foot is articulated to a framing which can be periectlyadapted to the short foot or leg. This framing has in every case the form and disposition required in order that the patients foot may maintain any convenient position.

. The prosthetic foot itself, according to my invention is hollow and made of metal or any it is divided in two difierent parts; the front part, corresponding to the toe cap, is articulated with the heel part, which is larger, by means of a hinge-joint which is fitted with an elastic device that gives it the necessary mobility during the various stages of walking. i

Inside the heel part of the prosthetic foot is the mechanism which brings about the movement to the whole of the prosthetic foot. This mechanism consists of: a cylinder which contains two elastic springs, between which is placed plied to a patient who suffers the piston which reciprocates at the interior of the cylinder; a double shock absorber or two shock absorbers which work jointly insuch a way that in one ofthe directions they exert a 5 slight resistance or controlling action and inthe other direction they exert a stronger resistance or more accentuated controlling or braking action.

If the prosthetic foot of my invention is apfrom a marked shortness of one leg, the cylinder, together with its piston and the operating rod, is placed be tween the axle at the ends of the levers oithe shock absorbers and the framing fastened. to the 5 leg or passive part of the apparatus. The upper part of the cylinder is articulated with this framing, and the free. end of the piston rod is articulated with the axle of the levers of the shock absorbers. The shock absorbers are solidly fixed on the sole in the inside. of the heel of the prosthetic foot. The cylinder serves as a connection between the framing and the prosthetic foot. Apart from this joint there is another articulation between the framing and a support solidly attached to the inside of the heel part of the prosthetic foot, which support is placedin front of the two shock absorbers. n r

In the passive part of the apparatus or framing there are some pieces, of leather forinstance,

which surround the leg and the front part of the foot, held by means of shoe laces which are fastened with appropriate clasps and eyelets.

In the case of total injury of the foot, the

framing, fixing support or passive part of the apparatus consists. of a rigid body, that surrounds what remains of the leg of the injured person and to this framing is coupled the" prosthetic foot. In this case the prosthetic foot may remain completely closed andits articulation or coupling with the framing, or passive part of the same, is done on both sides of the prosthetic leg, these articulations being at the level of the ankle of the opposite normal foot. The upper part of the cylinder is then joined by means of a special articulated device to a piece solidlyfastened at the rear wall of the support that contains the stump of the injured leg. l

The mechanism may also be inverted and the axle of the shock absorbers be fixedto the framing fastened to the leg, articulating the cylinder to a point of the sole of the prosthetic foot.

In both the case of marked shortness and of total injury of the foot, everything that represents the sole section in the prosthetic foot is coatedwith a soft material (caoutchouc, felt pressed cork, etc.) for the purpose of smoothing the shock against the ground and provide, at the same time, noiseless operation of the apparatus.

In the drawings are shown various forms of construction of the prosthetic foot of my invention.

Figure l is a side view, partly in section, of the prosthetic foot coupled to theframing that is fastened to what remains of the leg in the case of total injury of the foot.

Figure 2 is a side view, partly in section, of the lower part of the foot in Figure 1, seen from the opposite side.

Figure 3 is a longitudinal section of the lower part of the foot showing its mechanism.

Figure 4 is a longitudinal section of a prosthetic much resistance, but when the heel part of the footrises'because it rests upon the heel, the shock absorber exerts a l'llllICh weaker resistance or braking action.

" If the prosthetic foot is to be applied to a shortened-leg and Ioot, the shape of the framing foot showing a modification specially designed'to be applied in some cases of injury, and, finally,

Figure 5 is a side view of the support that is fastened to the patients leg inthe case of shortness the leginorderto 0 1 .1 VShQW igi "As shown in Figures 1, 2, 3' and 4, that is, for

cases of" injury, my invention comprises a prosthe in foot corhpbsedoi two parts, the toe part I ehit e heel part1, cgum d together by means "ofahinge-joint 3"and"an elastic device 4, such as, for instance, a spring.

"" Inside'the he i ert 2 of the prosthetic foot ithereiis attached a piece 5, the upper partof which is articulated to theframing s which is fastened itdthejie'g of the injured foot, h c articulation fl may .cdnsist Bf, for instance, a ball bearingjancl is at same level as the ankle of the normal toot." ""At both sides and somewhat behindthe piece 5 there is placed the shock absorber 8', solidly fixed eh sole and in thev heel part 2 of the prosthetic r e levers l fl'ari'd' I I or this shock absorber 'are'coupled to an axle l2, which at its central pert is articulated teth rod 13 that carries t e piston 14 ofthe'cyIinder l5. -irhe upper nd of this cylinder I5 is articulated .witih a piecellfi, solidly fixed to'the'rear Wall of the framing fi'thatsurround's thein jure d leg. The piston l4 of thepump'is set between twosprings If! and I8 placed'itrsidethe cylinderftherie being var ou's meansto regulate the tension of the lower 1 8 or the upper spring l 1 ihdependntly. gure 4 shows a' rnodification in the construc tion'fffhe prosthetic foot of my invention which diilei' example described beforeflbecause 15,] coupled tothe 'shock'absorber 8, instea dfof 'bei gdisoosed in a vertical direction, isdisposed a more or lesshor'izontal position aiqngthes le fthe' oet. rhe -epeiet e of this specially constructed ot exactlythe same as theon det A shot nin'Figiiresl to 3-, but thedi's- 'n' of thcylinder'in horizontal directionon th iee r thefootdiminishes th height or the inechahismso that th efpot' may be quite closed out e upper part andit can bemo're eas ly use '1 U dification of the prostheticfootfis suitabler cases in whichinjuryonly' afiects the'fo'fot b elowth 'ahkll I i v In this form of construction shown in Figure 4 'the'shock absorber '8, instead of being-fixed to the -sol"o f the foot mounted on the'principal exie' zr rert e letien and this axle 'is' j'oin'ed'to' the support or rigidfl'p'art which is fastened to the patients legby means of supporting' pieces 28 hired to a bridge" or"transverse"p;iece 252. 1 The cylinder [5 "placed ina more orlesfs horizontal position iriside'the foot and 'upon the so1e"'of the principal" p'art'of the "willbe' such as to permit the surrounding of the convenient position. With this object in view,

the said framing is constituted by rigid parts I!) (Figure 5)" articulated togetherjwh-ich arefa stened 'on' the shortened leg "20 and foot I by means of flexible pieces 2 2 whicliare' closed jby means of shoe 'la-ces'jclasps andeyel'ets.

In the rigid pieces [9; parts have been provided 23 and 24, which are'at'tached', respectivelyfto the cylinder [5 and to the base and la tcral 'wallfsof the rear inner segment of the'pros'thetic toot in this case of shortness? I N l After the foregoing statements it may be realized that those detailsin the construhtioii offihe apparatus which have no influence its essence are susceptible of variation. Asa consequence it may be constructed iii an'y'size with'thernali'erial or materials deemed convenient, beingapplicable for ashortnes's df'the "lower extremity or to is- -place the i'm'uredfoot. Itis also 'pos'sible' to make use of any type of shock absorber existing in the market, 'as well as to use the methodsdeemed moreadequate for joining together the diif'rent piecesof' th'e"apparatus'. I claim? l. A prosthetic foot for injured or short legs comprising a heel part'that'forms the bod'yfor v foot "and a forward part which forms the'erl'd and which is pivdtenyceanectedto the" heel Daft by means Ofahihg-Qi ht articulationin combination with"aspring';' heel part being pivotally connected to aifram ng which is attached 'to't'hejpat'ients res, and said heel part comprising in its"interiora shock-ehsorbing mechanism whose lever is articulated to the end of the rodof' api sto'n' sliding eihs-i ie of a cyl nder of a springpumn in'order t'o'sinhoth the movement of the foot upon'ilts point of articulation with the framing fastenedto the leg? '2. Q4 prosthetic foot as claims-din 'e' eihi ijemprising a support fixed upo'n theinterior partfof the sole of'the foot, said support homing thee'ie ofthe' shock absorbing mechanism, err-ether 'airle parallel to"the axlaofsa'id shock absorber aha pivotally' connecting the heel part ofthe foot to the framing fastenedto' the patients leg, a sprin'g pump consistingof a cylinder provided a piston actuatedbysprings, said piston slid'ing'ih the interior-"of the said cylinder, the rod of said piston being pivotally connected to-th'e "endbf the lever 'orthe shock absorber while the-free end of the cylinder is pivotally connected "to the framing fastened to the patients leg.

3. A prosthetic foot as claimed in claim l, comprising a framin orfixing piece'fa stened to'the patientfs leg, a support mounted onthispiece; a horizontal axle mounted on "this supporti and forming the rotating axle oftheshock-absorbe'r,

inside which reciprocates a piston actuated by v the piston rod being pivotally absorber and springs, the end of connected to the arm of the shock the free end of the cylinder being pivotally con- 3 nected to a support which is fixed to the sole --or inside part of the foot. y

4. A prosthetic foot as claimed in claim 1. which comprises a hinge-joint connection; between the two parts which form thefootincombination with a spring that engages support pieces fixed on the two parts of the foot tending to keep these two parts of the foot in the most open position.

5. A prosthetic foot as claimed in claim 1, in which the ;two parts, toe end and heel part of the prostheticfoot are coupled by means of a hingejoint subjected to the action of a spring, a shock absorbing mechanism having been fixed on the bottom'and in the interior of the heel part of the prosthetic foot.

6; A prosthetic foot as claimed in claim 1, which comprises a spring pump formed by a 1 cylinder inside which reciprocates a piston; two

springs located in the interior of the cylinder, and hearing by one of their ends upon the opposite sides of thepistonand by thelothcr end upon the two opposite endsoi the cylinder, and a rod :fixedtothis pistonthatfiprdtrudes from the cylinder andis pivotally connected to the arm of n the shock absorber.

7. 5 prosthetic foot as claimed in claim 1,

which comprises a framing or fixing piece that is fastened to the leg and foot of the patient in the case of a short leg, said fixing piece being composed of two parts connected by a hingejoint; a lower part, which corresponds to the toe 25 Number REFERENCES CITED 4 The following references are of record in the file of this patent:

UNITED STATES PATENTS Name Date 1,279,356 Kenney Sept. 17. 1918 

